tz racin Posted May 19, 2012 Report Share Posted May 19, 2012 lookin for sum help from ya guys i took my 4 mil alky banshee to the dyno this evening and first 2 passeswas 92 an 93 hp and it was it was really rich now prib lem is after first 2 runs@ 93 hp it dropped down to 82 to 85 hp not respondin to jettin changes and any timing past 8° and it loses bout 3 more hp, is it possible an electrical prob? motor is fresh any thoughts guys id apprieciate it TZ Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 19, 2012 Author Report Share Posted May 19, 2012 fouled plugs, I dont really know but its possible. Did you change them? YEPP SURE DID NO DIFFERENCE ON PLUGS , RICHENING IT UP MADE NO DIFFERENCE, SHEARER RDZ SMALL BORE DRAG PIPES. 18 CC DOME PWK 39 CARBS STOCK IGNITION SYSTEM , LIGHTEND FKYWHEEL ADJUSTABLE TIMING PLATE STRAIGHT CUTS STOCK RATIO , UNRESPONSIVE TO JETTING UNLESS U TRY To LEAN IT DOWN SOME THEN IT LOSE A COUPLE HP, AND IF U ADVANCE TIMING ANYWHERE PAST 8° IT LOSES 4 HP, COULD IT BE ELECTRICAL? TO MUCH LOAD THE DYNO IS DRAWING? THE BIKE SEEM TO RUNCH MUCH MUCH WARMER ON THE DYNO EVEN IF IT RICH U CANT KEEP YUR HANDS ON PIPES OR CYLS MORE THAN 5 SECONDS OR SO BUT OUT ON TRACK IT RUNS NOWHERE THAT DAMN HOT LOL! JUST TRYING FIND OUT WHAT THE HELL IS GOING ON IM WONDERING IF STATOR WDNT BAD AFTER THE FIRST 2 PASSES?? THANKS IN ADVANCE FOR HELP GUYS TZ Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 19, 2012 Author Report Share Posted May 19, 2012 Your dyno might need a repair or something. Dont they have to change the dyno brake system ever so often?? THATS EXACTLY MY THOUGHT BUD I DIDNT WANT TO SA ANYTTHING AND B RUDE BUT I THINK IM IMA HAVE TOO, I THINK THERE WAS TO MUCH LOAD ADJUSTED ON THE DYNO REALLY PULLIN A LOAD!AND IT S A DYNOJET DYNO HE SAYS CHANGE MY COMPLETE ELE TRICAL AND COME BACK , FOR THE HELL OF IT I HAVE AOTHER COMLETE ELECTRICAL SYSTEM TO PUT ON IT BUT I DOUBT THATS IT! NOW HERES ANOTHER THOUGHT THE REAR WHEELS AND RIMS THATHE SUPPLIED WHERE SHAKING AND VIBRATING LIKE CRAZY WHEN THE BKE CAME ON THE POWER ENOUGH THAT THE BIKE SHIFTED OVER APPROX SIX INCHES BUT THE BACK TIRES DID STAY ON THE DRUM THRU THE FULL RUNS BUT WOULDNT ONE THINK THE TIRES SHAKIN VOILENTLY WOULD ROB SUM ORSEPOWER LOL THANKS BUD TZ Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 19, 2012 Author Report Share Posted May 19, 2012 It just doesnt make sense that you were up to the 93 hp range and then all of a sudden you dropped to the low 80 hp range. Maybe pull the heads off to see what could be going on. You should check your spark and see if it looks strong or normal. If it does then its probably something with this guys dyno. I WAS SO DISQUSTEDTHAT I DIDNT EVEN STOP TO TAKE A PIC AT GRAPHI WAS IN SHOCK THAT WE MADE GOOD HP FIRST 2 PASSES THEN SHUT BIKE OFF AND TOOK MAIN JET DOWN FROM118 TO 116 AND WHEN WE STARTED BIKE UP FOR ROUND 2 WITH FIRST CHANGE WE LOST LIKE 8 HP SO WE WENT BACK TO ORIGINAL SET UP AND STILL NOTHING THE LOST HP.EVER CAME BACK, SLICKS WERE 15 LBS CLUTCH WAS GREAT NO SLIP whatsoever, did a compression test on dyno both showed 190 PSI EACH I DONT THINK TIRES WERE SLIPPING THAT I COULD TELL!! Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 19, 2012 Author Report Share Posted May 19, 2012 I WAS SO DISQUSTEDTHAT I DIDNT EVEN STOP TO TAKE A PIC AT GRAPHI WAS IN SHOCK THAT WE MADE GOOD HP FIRST 2 PASSES THEN SHUT BIKE OFF AND TOOK MAIN JET DOWN FROM118 TO 116 AND WHEN WE STARTED BIKE UP FOR ROUND 2 WITH FIRST CHANGE WE LOST LIKE 8 HP SO WE WENT BACK TO ORIGINAL SET UP AND STILL NOTHING THE LOST HP.EVER CAME BACK, SLICKS WERE 15 LBS CLUTCH WAS GREAT NO SLIP whatsoever, did a compression test on dyno both showed 190 PSI EACH I DONT THINK TIRES WERE SLIPPING THAT I COULD TELL!! IM GOIN TO SHOP NOW ILL CHECK SPARK AND REED PETALS BEFORE I DO ANYTHING Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 20, 2012 Author Report Share Posted May 20, 2012 well worked on shee all day and spark was nice and strong / consistent herss what i believe is foin on , a couple things i believe to b the culprit! aftef i checked spark i pulled cool head and domes offand found that my exhaust portshape on the roof at the window of port was to aggressive and the rings were chisseling on the port roof si i yanked cyls offreshaped exhaust ports and opened up thee entire port with shapeof course,chamfered and ran a hone thru the cyls and pu put new rings in it cut 10 off base of cyls 12 thou base gasket put in 18cc alky domes 48 thou squish 180 on gauge and and started up and heat cycled it it sounds 10 more times potent than b4 and this evening i took it out for a few blasts and it is overly strong to say the least, but what i believe i found roungwwas rings gettin chisseled. dome bowl area to small too much compression b4 so back to the dyno with my own rear dyno rims and tires that dont shake voilently lol tt was decinitly a horsepowe robber no matter what TZ Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 20, 2012 Author Report Share Posted May 20, 2012 i bet itll be at least 94 or better now im sure ,transfers are at the limits for no welding!!! Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 20, 2012 Author Report Share Posted May 20, 2012 oh yeah and what kind of pipes are you running? shearer rdz ouuta frame small drag pipes and as far as port timing goes il tell ya thia way and then u can do math from top of cyl 42.25 mm transfers and 25.25 mm exaust port with certain shapes and angles. using 795 piston 22 thou base gasket.custom 18cc dome, 13° angle 115 cut out.4 mil 115 rod crankat 500 ft sea level, vforce 3 modded, pwk carbs ser up for alky thanks for all the help buddy i appriciate the suggestions TZ RACIN Quote Link to comment Share on other sites More sharing options...
BANSHEE HP Posted May 20, 2012 Report Share Posted May 20, 2012 you mention the tires shaking real bad at high speed, all of our dyno tires are balanced. you get big time tire shake if theyre not. we also run 12psi in hoosier slicks and american racers. the bike getting hotter then usual, is there a high powered fan in the dyno room to point at ur radiator? whats the gearing? you talked about load, we simulate load with gearing. usually the biggest c/s and smallest rear sproket you have, or shoot for 90-100mph. and finally without the answers to those questions, i think your just lean. adding timing produces a hp drop, its getting hot, and the decline in hp on the third pull of three. one easy way i can tell if a bikes lean is the incriments the bike makes hp or loses hp in a group of 3-4 pulls. if the bike let say made 93 first pull, 92 the second, and like 85 on the third i would say that its lean. because on the thrid run the bike is now hot, too hot. now on the other hand a bike that gets on a makes 85 first pull, 90 the second and 92 the third. i would say its rich, the bike was getting up to temp on the first pulls and making good power on the last pull. now of course there are a list of other things i look at to determine lean or rich but generally if the bikes gains hp every pulls its rich, if it loses hp after each pull its lean. when you can stack dyno graphs on top of e/o you know your close on jetting. hope some of this helps Quote Link to comment Share on other sites More sharing options...
tz racin Posted May 20, 2012 Author Report Share Posted May 20, 2012 you mention the tires shaking real bad at high speed, all of our dyno tires are balanced. you get big time tire shake if theyre not. we also run 12psi in hoosier slicks and american racers. the bike getting hotter then usual, is there a high powered fan in the dyno room to point at ur radiator? whats the gearing? you talked about load, we simulate load with gearing. usually the biggest c/s and smallest rear sproket you have, or shoot for 90-100mph. and finally without the answers to those questions, i think your just lean. adding timing produces a hp drop, its getting hot, and the decline in hp on the third pull of three. one easy way i can tell if a bikes lean is the incriments the bike makes hp or loses hp in a group of 3-4 pulls. if the bike let say made 93 first pull, 92 the second, and like 85 on the third i would say that its lean. because on the thrid run the bike is now hot, too hot. now on the other hand a bike that gets on a makes 85 first pull, 90 the second and 92 the third. i would say its rich, the bike was getting up to temp on the first pulls and making good power on the last pull. now of course there are a list of other things i look at to determine lean or rich but generally if the bikes gains hp every pulls its rich, if it loses hp after each pull its lean. when you can stack dyno graphs on top of e/o you know your close on jetting. hope some of this helps HEY HP NO RIMS AND TIRES WERE NOT BALANCE AT ALL. AND SHOOK LIKE CRAZY ENOUGH TO MOVE BIKE OVER ON DYNO FRONT END AS WELL AND THERE WAS A FAN IN THE DYNO TRAILER BUT IT SEEMEX LIKE IT COULDNT KEEP UP WITH AIRING OUT AREA A.D BIKE WAZ USING ITS SPENT EXHAUST GASES AND MOTOR WAS BREATHING ITSELF RECYCLING ITSELF AIR WISE IF U WILLI! JETTIN WAS DAMN NEAR ON WHEN I GOT THEDE AFTED 2 FIRST PULLS WE CHANGED ET AND ALSO TURNED PJ DOWN AND THATS WHEN IT LOST POWER, SO WE WENT BACK TO ORIGINAL SETTINGSBUT HP WAZ LOST, GEARING WAS 16 40 I THOUGHT THAT WAS ADAQUATE FOR DYNO WHAT DO U THINK??XO U THINK THERE WAS POWER LOSE AT ALL WITH WHEELS SHAKING LIKE THAT BEING TRANSFERED BACK TO MOTOR?? THANKS TZ Quote Link to comment Share on other sites More sharing options...
RadarRacing Posted May 29, 2012 Report Share Posted May 29, 2012 They will do that if the pipe is holding too much heat. There is no shearer rdz pipe, its either shearers or rdzs. If I thought the pipe held too much heat I would add a lot more fuel and add a little timing as well regardless of how rich it seemed. You should be able to get 3 to 5 seconds of hard pull on a dyno. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted June 2, 2012 Report Share Posted June 2, 2012 hey just outts curiosity did you used to run 300ft down in pa,i ran a few times up there visiting my friends the mollners and i know a few guys came down from niagra falls Quote Link to comment Share on other sites More sharing options...
tz racin Posted June 3, 2012 Author Report Share Posted June 3, 2012 yes with one of my first banshees built a fiod while back Quote Link to comment Share on other sites More sharing options...
CP5899 Posted June 7, 2012 Report Share Posted June 7, 2012 I've had my dyno for over 8 years and never had problems with calibrations or the dyno being off. I've had wide band o2 sensors go bad during a dyno, but thats about it. I've had many people complain saying the dyno was off, due to them not making the power they thought they would/should. But, in fact the dyno is a tool and if properly maintained it shouldn't have problems. At least mine hasn't. As to your issue with the bike making 93-94 on the the first couple runs and then dropping off to low 80's. I have seen this many times and will explain what it was in the cases that I've seen. I didn't read through this whole post so I'm sorry if I'm duplicating what others have stated. Anyway, a couple banshees that come to mind that I've had the exact same issue as what you described (90's first two pulls then drops to low 80's) also were alky 4mm stock cylinder motors. (not sure if you have stock cyl or aftermarket). After the bike would drop down to the 80-83 hp it wouldn't make more power with jet changes or timing changes due to the bike being so hot. What I ended up figuring on these particular bikes is that the style drag pipes they were running were a small chamber style pipe. Not a large chamber pipe like a cpi or shearer. That being said the small chamber pipe would build so much heat on these particular bikes after a run or two that they would drop 10 hp due to being so hot. To test the idea we put a set of small bore (out of frame) cpi pipes I had for one of my stoke cylinder bikes onto the bikes I was dynoing. After the pipe change, the power was back up and we could make 5-6 pulls before power would start to fall off. I'm not sure what pipes you are running or all the details of your motor as I skimmed through the OP, but that could be something to look into. Every motor is different and there are tons of variables, but maybe this will give you a few more things to look for if you haven't found the problem yet. cp Quote Link to comment Share on other sites More sharing options...
possum Posted June 7, 2012 Report Share Posted June 7, 2012 ^^^ good info on pipe heat. Quote Link to comment Share on other sites More sharing options...
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